package course.d1215;

public class demo02 {
    public static void main(String[] args) {
        StringBuilder s = new StringBuilder("false");
        s.reverse();
        System.out.println(s);
        s = s.append(false);
        System.out.println(s);
        s.setCharAt(0,'s');
        s.insert(0,1);
        int index = s.lastIndexOf("s");
        System.out.println(index);
        System.out.println(s);
        int index1 = s.indexOf("s");
        System.out.println(index1);
        s.setLength(22);

        s.append(true);

        s.setCharAt(0,'A');
        System.out.println(s);
    }
}
